This project elucidates the fundamental molecular architecture of heparins/heparan sulfates and studies the molecular basis of their specific modulation of proteins and cell membranes in diverse normal and diseased physiological systems, using various physical, biochemical, and biological approaches. We examined heparins as a mechanism of viral infectivity, studied structured on structure-function relations of a heparin-mimetic pharmaceutical composed of a mixture of sulfated oligoxylans (S-oligoS), which as heparin, inhibits the infectivity of HIV in vitro: 1) We established that the capacity to inhibit cytotoxity and sync-tium-forming infectivity of HIV-1 was governed by a structural specificity (HD 01315-01). Now, we find that the two antiviral capacities also expressed differential structural requirements (e.g., mass greater than or equal to about 5400 and about >4500, respectively). 2) We established that the minimal-sized potent antiviral component, CpF, was separable from S-oligos with anticoagulation activity against thrombin. And that the SoligoS also exhibit structural specificity in various anticoagulation reactions. 3) We showed S-oligoS contained multiple a D-GIcA moieties, that the Proton NMR analysis confirms this. The data indicate a new model structure, a tetrasaccharide repeat of three b 1-4 linked sulfated xylose units containing an a 1-2 linked 40Me sulfated D-GlcA, and in a fraction of S-oligoS yield & viral-inhibitory material (about 900mg) without anticoagulant activity. [Total expected yield = about 900 mg.] Endotoxin assays showed no significant contamination. We are now able to develop a medium pressure LC system with good manufacturing practices for a large scale preparation of CpF or S-oligoS with specificity for other heparin-mimetic functions.